Twentieth-century global-mean sea-level rise: is the whole greater than the sum of the parts?

Confidence in projections of global-mean sea level rise (GMSLR) depends on an ability to account for GMSLR during the twentieth century. There are contributions from ocean thermal expansion, mass loss from glaciers and ice sheets, groundwater extraction, and reservoir impoundment. Progress has been made toward solving the “enigma” of twentieth-century GMSLR, which is that the observed GMSLR has previously been found to exceed the sum of estimated contributions, especially for the earlier decades. The authors propose the following: thermal expansion simulated by climate models may previously have been underestimated because of their not including volcanic forcing in their control state; the rate of glacier mass loss was larger than previously estimated and was not smaller in the first half than in the second half of the century; the Greenland ice sheet could have made a positive contribution throughout the century; and groundwater depletion and reservoir impoundment, which are of opposite sign, may have been approximately equal in magnitude. It is possible to reconstruct the time series of GMSLR from the quantified contributions, apart from a constant residual term, which is small enough to be explained as a long-term contribution from the Antarctic ice sheet. The reconstructions account for the observation that the rate of GMSLR was not much larger during the last 50 years than during the twentieth century as a whole, despite the increasing anthropogenic forcing. Semiempirical methods for projecting GMSLR depend on the existence of a relationship between global climate change and the rate of GMSLR, but the implication of the authors' closure of the budget is that such a relationship is weak or absent during the twentieth century.

Why did democracy become the preferred political regime only in the twentieth century?

A Democracia Tornou-Se a Forma Preferida de Governo Apenas no Século Vinte. a Busca por Motivos Racionais para Entendermos a Razão não é Suficiente. o Autor Procura por um Fato Histórico Novo que Tenha Levado a Essa Mudança de Preferência, Baseado Sucessivamente na Revolução Capitalista e na Perda Gradual do Medo da Expropriação Pela Burguesia. a Revolução Capitalista que Mudou o Modo de Apropriação do Excedente, da Violência para o Mercado, é a Primeira Condição Necessária. Representa Também a Transição do Estado Absoluto para o Estado Liberal. a Segunda Condição é o Desaparecimento do Medo da Expropriação, Permitindo a Transição do Regime Liberal para o Regime Liberal-Democrático. Depois de Estabelecer Estas Duas Condições, ou Estes Dois Fatos Históricos Novos, o Regime Democrático Tornou-Se Rational Choice para Todas as Classes. para os Capitalistas, Democracia é Agora a Forma de Governo que Melhor Assegura o Direito À Propriedade e Aos Contratos. para os Trabalhadores, é a Forma de Governo que Melhor Assegura o Aumento de Salários com Lucros

The economic development of Latin America in the twentieth century

Includes bibliography

Returning to an external debate: the terms of trade for commodities in the twentieth century

Includes bibliography

The terms of trade for commodities in the twentieth century

Includes bibliography

A study of return migration to the Organisation of Eastern Caribbean States (OECS) territories and the British Virgin Islands in the closing years of the twentieth century: implications for social policy

Includes bibliography

Latin American economic growth in the late twentieth century: evidence and interpretation

Includes bibliography

IMMIGRATION, THE AMERICAN WEST, AND THE TWENTIETH CENTURY: GERMAN FROM RUSSIA, OMAHA INDIAN, AND VIETNAMESE-URBAN VILLAGERS IN LINCOLN, NEBRASKA

The North American West is a culturally and geographically diverse region that has long been a beacon for successive waves of human immigration and migration. A case in point, the population of Lincoln, Nebraska -- a capital city on the eastern cusp of the Great Plains -- was augmented during the twentieth century by significant influxes of Germans from Russia, Omaha Indians, and Vietnamese. Arriving in clusters beginning in 1876, 1941, and 1975 respectively, these newcomers were generally set in motion by dismal economic, social, or political situations in their sending nations. Seeking better lives, they entered a mainstream milieu dominated by native-born Americans -- most part of a lateral migration from Iowa, Illinois, and Pennsylvania -- who only established their local community in 1867. While this mainstream welcomed their labor, it often eschewed the behaviors and cultural practices ethnic peoples brought with them. Aware but not overly concerned about these prejudices, all three groups constructed or organized distinct urban villages. The physical forms of these enclaves ranged from homogeneous neighborhoods to tight assemblies of relatives, but each suited a shared preference for living among kinspeople. These urban villages also served as stable anchors for unique peoples who were intent on maintaining aspects of their imported cultural identities. Never willing to assimilate to mainstream norms, urban villagers began adapting to their new milieus. While ethnic identity constructions in Lincoln proved remarkably enduring, they were also amazingly flexible. In fact, each subject group constantly negotiated their identities in response to interactions among particular, cosmopolitan, and transnational forces. Particularism refers largely to the beliefs, behaviors, and organizational patterns urban villagers imported from their old milieus. Cosmopolitan influences emanated from outside the ethnic groups and were dictated largely but not exclusively by the mainstream. Transnationalism is best defined as persistent, intense contact across international boundaries. These influences were important as the particularism of dispersed peoples was often reinforced by contact with sending cultures. Adviser: John. R. Wunder

Chemistry and Chemical Education Through Text and Image: Analysis of Twentieth Century Textbooks Used in Brazilian Context

Assuming that textbooks give literary expression to cultural and ideological values of a nation or group, we propose the analysis of chemistry textbooks used in Brazilian universities throughout the twentieth century. We analyzed iconographic and textual aspects of 31 textbooks which had significant diffusion in the context of Brazilian universities at that period. As a result of the iconographic analysis, nine categories of images were proposed: (1) laboratory and experimentation, (2) industry and production, (3) graphs and diagrams, (4) illustrations related to daily life, (5) models, (6) illustrations related to the history of science, (7) pictures or diagrams of animal, vegetable or mineral samples, (8) analogies and (9) concepts of physics. The distribution of images among the categories showed a different emphasis in the presentation of chemical content due to a commitment to different conceptions of chemistry over the period. So, we started with chemistry as an experimental science in the early twentieth century, with an emphasis change to the principles of chemistry from the 1950s, culminating in a chemistry of undeniable technological influence. Results showed that reflections not only on the history of science, but on the history of science education, may be useful for the improvement of science education.

Agricultural Genetics and Plant Breeding in Early Twentieth-Century Italy

This thesis is about plant breeding in Early 20th-Century Italy. The stories of the two most prominent Italian plant-breeders of the time, Nazareno Strampelli and Francesco Todaro, are used to explore a fragment of the often-neglected history of Italian agricultural research. While Italy was not at the forefront of agricultural innovation, research programs aimed at varietal innovation did emerge in the country, along with an early diffusion of Mendelism. Using philosophical as well as historical analysis, plant breeding is analysed throughout this thesis as a process: a sequence of steps that lays on practical skills and theoretical assumptions, acting on various elements of production. Systematic plant-breeding programs in Italy started from small individual efforts, attracting more and more resources until they became a crucial part of the fascist regime's infamous agricultural policy. Hybrid varieties developed in the early 20th century survived World War II and are now ancestors of the varieties that are still cultivated today. Despite this relevance, the history of Italian wheat hybrids is today largely forgotten: this thesis is an effort to re-evaluate a part of it. The research did allow previously unknown or neglected facts to emerge, giving a new perspective on the infamous alliance between plant-breeding programs and the fascist regime. This thesis undertakes an analysis of Italian plant-breeding programs as processes. Those processes had a practical as well as a theoretical side, and involved various elements of production. Although a complete history of Italian plant breeding still remains to be written, the Italian case can now be considered along with the other case-studies that other scholars have developed in the history of plant breeding. The hope is that this historical and philosophical analysis will contribute to the on-going effort to understand the history of plants.